nixpkgs/doc/release-notes/rl-2505.section.md

# Nixpkgs 25.05 (2025.05/??) {#sec-nixpkgs-release-25.05}

## Backward Incompatibilities {#sec-nixpkgs-release-25.05-incompatibilities}

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### Titanium removed {#sec-nixpkgs-release-25.05-incompatibilities-titanium-removed}

- `titaniumenv`, `titanium`, and `titanium-alloy` have been removed due to lack of maintenance in Nixpkgs.

## Nixpkgs Library {#sec-nixpkgs-release-25.05-lib}

### Breaking changes {#sec-nixpkgs-release-25.05-lib-breaking}

- Structure of the `functor` of some types has changed. `functor` is an implementation detail and should not be relied upon. If you did rely on it let us know in this [PR](https://github.com/NixOS/nixpkgs/pull/363565).
  - [`lib.types.enum`](https://nixos.org/manual/nixos/unstable/#sec-option-types-basic): Previously the `functor.payload` was the list of enum values directly. Now it is an attribute set containing the values in the `values` attribute.
  - [`lib.types.separatedString`](https://nixos.org/manual/nixos/unstable/#sec-option-types-string): Previously the `functor.payload` was the seperator directly. Now it is an attribute set containing the seperator in the `sep` attribute.

### Deprecations {#sec-nixpkgs-release-25.05-lib-deprecations}

`functor` is an implementation detail and should not be relied upon, but since its status wasn't clear and it has had some use cases without alternatives, changes are being handled as gracefully as possible. Deprecations within functor:
- `functor.wrapped` is now deprecated for some types and using it will give a warning with migration instructions. It is deprecated for these types:
    - `lib.types.attrsWith`